When heavy duty truck shoe brake shoes become worn, it is necessary to remove and then replace the fibrous pads. This is generally accomplished by removing the rivets one or a few at a time. Generally, there are two or more rows of rivets securing the fibrous pad to the base of the brake shoe. One typical design of brake shoes has thirty-two (32) rivets, eight rows of four rivets each. Generally, it takes much time and labor including a considerable number of machine operations to remove all of the rivets.
It is known in the prior art to use manually actuated presses having a cam surface that forces a plurality of punches to remove the rivets. Such systems are deficient in several ways. First, they must be individually tailored to the particular type of brake shoe which is being repaired. Various brake shoes may have different numbers of rivets, and it is somewhat limiting for the press to operate with a fixed number of rivets. Further, the prior art presses punch all of the rivets with a single stroke. Brake shoes generally extend along an arc, and rivets near the ends of the arc tend to be deformed by the force on the center of the arc caused when the rivets are removed.
It is therefore an object of the present invention to design a brake shoe rivet press which will remove all rivets from the corresponding brake shoe in one hit or in a single operation thereby resulting in a savings in time and labor.
It is further an object of the present invention to design a press in which two strokes are used. A first stroke forces the rivets from the center of the arc, and a subsequent stroke forces all of the rivets out of the brake shoe. Also, it is an object of the present invention to disclose such a press that may be tailored to repair brake shoe having varying numbers of rivets.